On the East. Komsomolets Island from Cape Molotov to South Eastern Cape; thence to Cape Vorochilov, Oktiabrskaya Revolutziya Island to Cape Anuchin. Then to Cape Unslicht on Bolshevik Island. Bolshevik Island to Cape Yevgenov. Thence to Cape Pronchisthehev on the main land (see Russian chart No. 1484 of the year 1935).

The Kara Sea was formerly known as Oceanus Scythicus or Mare Glaciale and it appears with these names in old 16th century maps. Since it is closed by ice most of the year it remained largely unexplored until the late nineteenth century.

In 1736–1737 Russian Admiral Stepan Malygin undertook a voyage from Dolgiy Island in the Barents Sea. The two ships in this early expedition were the Perviy, under Malygin's command and the Vtoroy under Captain A. Skuratov. After entering the little-explored Kara Sea, they sailed to the mouth of the Ob River. Malygin took careful observations of these hitherto almost unknown areas of the Russian Arctic coastline. With this knowledge he was able to draw the first somewhat accurate map of the Arctic shores between the Pechora River and the Ob River.

In 1878, Finnish explorer Adolf Erik Nordenskiöld on ship Vega sailed across the Kara Sea from Göteborg, along the coast of Siberia, and despite the ice packs, got to 180° longitude by early September. Frozen in for the winter in the Chukchi Sea, Nordenskiöld waited and bartered with the local Chukchi people. The following July, the Vega was freed from the ice, and continued to Yokohama, Japan. He became the first to force the Northeast Passage. The largest group of islands in the Kara Sea, the Nordenskiöld Archipelago, has been named in his honour. The year 1912 was a tragic one for Russian explorers in the Kara Sea. In that fateful year unbroken consolidated ice blocked the way for the Northern Sea Route and three expeditions that had to cross the Kara Sea became trapped and failed: Sedov's on vessel St. Foka, Brusilov's on the St. Anna, and Rusanov's on the Gercules. Georgy Sedov intended to reach Franz Josef Land on ship, leave a depot over there, and sledge to the pole. Due to the heavy ice the vessel could only reach Novaya Zemlya the first summer and wintered in Franz Josef Land. In February 1914 Sedov headed to the North Pole with two sailors and three sledges, but he fell ill and died on Rudolf Island. Georgy Brusilov attempted to navigate the Northeast Passage, was trapped in the Kara Sea, and drifted northward for more than two years reaching latitude 83° 17' N. Thirteen men, headed by Valerian Albanov, left the vessel and started across the ice to Franz Josef Land, but only Albanov and one sailor (Alexander Konrad) survived after a gruesome three-month ordeal. The survivors brought the ship log of St. Anna, the map of her drift, and daily meteorological records, but the destiny of those who stayed onboard remains unknown. In the same year the expedition of Vladimir Rusanov was lost in the Kara Sea. The prolonged absence of those three expeditions stirred public attention, and a few small rescue expeditions were launched, including Jan Nagórski's five air flights over the sea and ice from the NW coast of Novaya Zemlya.

After the Russian Revolution in 1917, the scale and scope of exploration of the Kara Sea increased greatly as part of the work of developing the Northern Sea Route. Polar stations, of which five already existed in 1917, increased in number, providing meteorologic, ice reconnaissance, and radio facilities. By 1932 there were 24 stations, by 1948 about 80, and by the 1970s more than 100. The use of icebreakers and, later, aircraft as platforms for scientific work was developed. In 1929 and 1930 the Icebreaker Sedov carried groups of scientists to Severnaya Zemlya, the last major piece of unsurveyed territory in the Soviet Arctic; the archipelago was completely mapped under Georgy Ushakov between 1930 and 1932.

Particularly worth noting are three cruises of the Icebreaker Sadko, which went farther north than most; in 1935 and 1936 the last unexplored areas in the northern Kara Sea were examined and small and elusive Ushakov Island was discovered.

In the summer of 1942, German Kriegsmarine warships and submarines entered the Kara Sea to destroy as many Russian vessels as possible. This naval campaign was named "Operation Wunderland". Its success was limited by the presence of ice floes, as well as bad weather and fog. These effectively protected the Soviet ships, preventing the damage that could have been inflicted on the Soviet fleet under fair weather conditions.

There is concern about radioactive contamination from nuclear waste the former Soviet Union dumped in the sea and the effect this will have on the marine environment. According to an official "White Paper" report compiled and released by the Russian government in March 1993, the Soviet Union dumped six nuclear submarine reactors and ten nuclear reactors into the Kara Sea between 1965–1988.[6] Solid high and low-level wastes unloaded from Northern Fleet nuclear submarines during reactor refuelings, were dumped in the Kara Sea, mainly in the shallow fjords of Novaya Zemlya, where the depths of the dumping sites range from 12 to 135 meters, and in the Novaya Zemlya Trough at depths of up to 380 meters. Liquid low-level wastes were released in the open Barents and Kara Seas. A subsequent appraisal by the International Atomic Energy Agency showed that releases are low and localized from the 16 naval reactors (reported by the IAEA as having come from seven submarines and the icebreaker Lenin) which were dumped at five sites in the Kara Sea. Most of the dumped reactors had suffered an accident.[7]

The Soviet submarine K-27 was scuttled in Stepovogo Bay with its two reactors filled with spent nuclear fuel. At a seminar in February 2012 it was revealed that the reactors on board the submarine could re-achieve criticality and explode (a buildup of heat leading to a steam explosion vice nuclear). The catalogue of waste dumped at sea by the Soviets, according to documents seen by Bellona, includes some 17,000 containers of radioactive waste, 19 ships containing radioactive waste, 14 nuclear reactors, including five that still contain spent nuclear fuel; 735 other pieces of radioactively contaminated heavy machinery, and the K-27 nuclear submarine with its two reactors loaded with nuclear fuel.[8]